Every time I try to convert a Windows-Legacy library to Windows it fails with the “collection was modified” error.
After deleting the project.json file, opening one of the XAMLs, and redoing the dependencies, then I can open it. But I would publish it and then couldn’t find the library in Manage Packages.
I discovered this is because UiPath sets it back to a process, not a library, when recreating the project.json file.
No problem, I thought, I’ll just edit project.json and set it back to library. As soon as I do that, I can’t open it - again getting the “collection was modified” error.
So I put project.json back to process, then opened it. In the Design ribbon, at the top I clicked Export As, and selected Library.
Now I am able to open it as a process, and when I publish it it’s correctly published as a library and visible in Manage Packages.
Hope this helps someone else not have to bang their head against the same wall I’ve been banging mine against for the last 2 hours.